A new acidic myotoxic, anti-platelet and prostaglandin I2 inductor phospholipase A2 isolated from Bothrops moojeni snake venom.
Phospholipase A2 (PLA2, EC 3.1.1.4), a major component of snake venoms, specifically catalyzes the hydrolysis of fatty acid ester bonds at position 2 of 1,2-diacyl-sn-3-phosphoglycerides in the presence of calcium. This article reports the purification and biochemical/functional characterization of BmooTX-I, a new myotoxic acidic phospholipase A2 from Bothrops moojeni snake venom. The purification of the enzyme was carried out through three chromatographic steps (ion-exchange on DEAE-Sepharose, molecular exclusion on Sephadex G-75 and hydrophobic chromatography on Phenyl-Sepharose). BmooTX-I was found to be a single-chain protein of 15,000 Da and pI 4.2. The N-terminal sequence revealed a high homology with other acidic Asp49 PLA2s from Bothrops snake venoms. It displayed a high phospholipase activity and platelet aggregation inhibition induced by collagen or ADP. Edema and myotoxicity in vivo were also induced by BmooTX-I. Analysis of myotoxic activity was carried out by optical and ultrastructural microscopy, demonstrating high levels of leukocytary infiltrate. Previous treatment of BmooTX-I with BPB reduced its enzymatic and myotoxic activities, as well as the effect on platelet aggregation. Acidic myotoxic PLA2s from Bothrops snake venoms have been little explored and the knowledge of its structural and functional features will be able to contribute for a better understanding of their action mechanism regarding enzymatic and toxic activities.
Santos-Filho
Norival A
NA
Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, FCFRP-USP, Ribeirão Preto, SP, Brazil.
Silveira
Lucas B
LB
Oliveira
Clayton Z
CZ
Bernardes
Carolina P
CP
Menaldo
Danilo L
DL
Fuly
André L
AL
Arantes
Eliane C
EC
Sampaio
Suely V
SV
Mamede
Carla C N
CC
Beletti
Marcelo E
ME
de Oliveira
Fábio
F
Soares
Andreimar M
AM
D000595:Amino Acid Sequence; D000704:Analysis of Variance; D000818:Animals; D017837:Bothrops; D002852:Chromatography, Ion Exchange; D003435:Crotalid Venoms / Q000737:chemistry*; D004487:Edema; D011464:Epoprostenol / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D007525:Isoelectric Focusing; D008297:Male; D051379:Mice; D008969:Molecular Sequence Data; D009132:Muscles / Q000187:drug effects* / Q000473:pathology; D054467:Phospholipases A2 / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism* / Q000633:toxicity*; D010975:Platelet Aggregation Inhibitors / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism / Q000633:toxicity; D016415:Sequence Alignment; D013696:Temperature; D015533:Transcriptional Activation
D003435:Crotalid Venoms; D010975:Platelet Aggregation Inhibitors; D011464:Epoprostenol; D054467:Phospholipases A2